Nasa Takes Probe Off Pad For Repairs

The Air Conditioning System Tore Insulation In A Miniprobe Inside The Plutonium-laden Cassini Probe Bound For Saturn.

September 4, 1997|By Seth Borenstein of The Sentinel Staff

CAPE CANAVERAL — A too-strong air conditioner probably will do what nuclear protesters have been unable to do so far: delay next month's launch of NASA's plutonium-laden Cassini probe.

A cooling system that pumped air three times stronger than intended tore insulation in a miniprobe inside Cassini. The damage forced NASA to remove Cassini from its perch atop a Titan IV-B rocket for a quick patch job, officials said Wednesday.

The $3.3 billion project was scheduled to launch from Cape Canaveral Air Station on Oct. 6 but probably will be delayed until mid-October, NASA officials said.

But if there is more damage than expected, it could force NASA to miss its main launch opportunity, which ends Nov. 4. If that happens, it would take 27 more months for Cassini to reach Saturn and its moons and cost NASA about $120 million more, program manager Richard Spehalski said.

Cassini was placed on its rocket Aug. 28. The next day NASA noticed the air conditioner that cools 34 radioactive heaters inside the miniprobe was pumping air at more than 400 mph. That probe separates from Cassini and plummets to Saturn's moon Titan.

On Tuesday, officials realized the blasting air caused a 2-inch rip in foam-and-foil insulation.

The big concern is that the ripped insulation would contaminate the rest of the spacecraft's delicate instruments.

''It's very disappointing, but we're dealing with it,'' said Hamid Hassan, project manager for the miniprobe.

Technicians will try to fix the rip with spare insulation, Hassan said. The work probably will cost less than $20,000 in overtime.

Cassini carries about 72 pounds of plutonium as an energy source, the most nuclear fuel launched into space.

A protest movement opposing the launch has gathered more than 30,000 signatures. The group, which is concerned that a launch accident could result in the release of radioactive material, plans nearly daily protests. Organizers said the launch delay will not stop their effort to keep Cassini grounded permanently.

''They may have a no-go, but we are still go,'' said Bruce Gagnon of the Florida Coalition for Peace and Justice, leader of anti-Cassini forces. ''I think the universe is speaking and sending messages to NASA that they shouldn't really do this.''

Spehalski said not only is Cassini safe, but the problem has nothing to do with its nuclear fuel.

''It does not represent anything that would compromise the ability of launching safely,'' he said.